The concept of glaciation, from French glaciation, refers to the process that leads to formation of glaciers: large ice masses. The term is also used in the field of geology to refer to the ice advance over large areas of the continents, a fact that was repeated at different times throughout history.
In this sense, the glaciation is a period characterized by a temperature drop leading to expansion of glaciers and continental ice. It is believed that there were four or more ice ages in the past of our planet.
The Huronian glaciation, which developed between 2,400 and 2.1 billion years back, it was the first and most extensive ice ages. Its origins are linked to the metabolic action of cyanobacteria, which would have released oxygen to the atmosphere and altered the balance until then existing.
The ice age of the Cryogenic period, meanwhile, was carried out between 850 and 635 million years ago. According to scientists, this glaciation was the most intense and, according to some theories, it froze the entirety of the Land.
The Andean-Saharan glaciation (completed between 460 and 430 million years back), the Karoo glaciation (Come in 350 and 250 million years) and the Quaternary glaciation (started about two and a half million years ago) are other of the stages recognized by specialists.
It is important to mention that the Quaternary glaciation keep going. The existence of the polar caps and glaciers that occupy about 10% of the earth’s surface is a testimony to the phenomenon.